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1.
Transl Anim Sci ; 7(1): txad118, 2023.
Article in English | MEDLINE | ID: mdl-38023419

ABSTRACT

Haemonchus contortus is the most pathogenic blood-feeding parasitic in sheep, causing anemia and consequently changes in the color of the ocular conjunctiva, from the deep red of healthy sheep to shades of pink to practically white of non-healthy sheep. In this context, the Famacha method has been created for detecting sheep unable to cope with the infection by H. contortus, through visual assessment of ocular conjunctiva coloration. Thus, the objectives of this study were (1) to extract ocular conjunctiva image features to automatically classify Famacha score and compare two classification models (multinomial logistic regression-MLR and random forest-RF) and (2) to evaluate the applicability of the best classification model on three sheep farms. The dataset consisted of 1,156 ocular conjunctiva images from 422 animals. RF model was used to segment the images, i.e., to select the pixels that belong to the ocular conjunctiva. After segmentation, the quantiles (1%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, and 99%) of color intensity in each image channel (red, blue, and green) were determined and used as explanatory variables in the classification models, and the Famacha scores 1 (non-anemic) to 5 (severely anemic) were the target classes to be predicted (scores 1 to 5, with 162, 255, 443, 266, and 30 images, respectively). For objective 1, the performance metrics (precision and sensitivity) were obtained using MLR and RF models considering data from all farms randomly split. For objective 2, a leave-one-farm-out cross-validation technique was used to assess prediction quality across three farms (farms A, B, and C, with 726, 205, and 225 images, respectively). The RF provided the best performances in predicting anemic animals, as indicated by the high values of sensitivity for Famacha score 3 (80.9%), 4 (46.2%), and 5 (60%) compared to the MLR model. The precision of the RF was 72.7% for Famacha score 1 and 62.5% for Famacha score 2. These results indicate that is possible to successfully predict Famacha score, especially for scores 2 to 4, in sheep via image analysis and RF model using ocular conjunctiva images collected in farm conditions. As expected, model validation excluding entire farms in cross-validation presented a lower prediction quality. Nonetheless, this setup is closer to reality because the developed models are supposed to be used across farms, including new ones, and with different environments and management conditions.

2.
Animals (Basel) ; 13(3)2023 Jan 21.
Article in English | MEDLINE | ID: mdl-36766263

ABSTRACT

This study investigated the feasibility of using easy-to-measure phenotypic traits to predict sheep resistant, resilient, and susceptible to gastrointestinal nematodes, compared the classification performance of multinomial logistic regression (MLR), linear discriminant analysis (LDA), random forest (RF), and artificial neural network (ANN) methods, and evaluated the applicability of the best classification model on each farm. The database comprised 3654 records of 1250 Santa Inês sheep from 6 farms. The animals were classified into resistant (2605 records), resilient (939 records), and susceptible (110 records) according to fecal egg count and packed cell volume. A random oversampling method was performed to balance the dataset. The classification methods were fitted using the information of age class, the month of record, farm, sex, Famacha© degree, body weight, and body condition score as predictors, and the resistance, resilience, and susceptibility to gastrointestinal nematodes as the target classes to be predicted considering data from all farms randomly. An additional leave-one-farm-out cross-validation technique was used to assess prediction quality across farms. The MLR and LDA models presented good performances in predicting susceptible and resistant animals. The results suggest that the use of readily available records and easily measurable traits may provide useful information for supporting management decisions at the farm level.

3.
Animals (Basel) ; 12(24)2022 Dec 08.
Article in English | MEDLINE | ID: mdl-36552393

ABSTRACT

This study evaluated the influence of environmental temperature on thermoregulation, hormonal, and hematological characteristics in Caracu cattle. Blood samples, hair length, coat and muzzle colors, rectal (RT), and surface temperatures were collected from 48 males and 43 females before (morning) and after sun exposure for eight hours (afternoon). Infrared thermography (IRT) was used to identify superficial temperature that exhibits a high correlation with RT. Hematological parameters, hormone concentrations, RT, and the superficial temperature obtained by IRT that exhibited the highest correlation with RT were evaluated by variance analysis. Regarding IRT, the lower left side of the body (LS) showed the highest correlation with the RT. Interaction between period and sex was observed for LS, cortisol, and eosinophils. Cortisone, progesterone, and RT were influenced by period and sex. Neutrophils and segmented neutrophils were influenced by the period, which showed the highest concentrations after sun exposure. Platelets, leukocytes, lymphocytes, and monocytes were influenced by sex. Heat stress changes several physiological characteristics where males and females exhibited differences in their responses to heat stress. Furthermore, most characteristics evaluated remained within the regular values observed for taurine Creole breeds, showing that Caracu is adapted to tropical climates.

4.
Animals (Basel) ; 12(22)2022 Nov 18.
Article in English | MEDLINE | ID: mdl-36428423

ABSTRACT

Feed and water efficiency are important traits to improve beef cattle production's economic and environmental sustainability. This study evaluated residual feed intake (RFI) and residual water intake (RWI) and their relationship with performance, ingestive behavior, and carcass traits in Caracu beef cattle. The data were analyzed using a generalized linear model with least squares means. The ingestive behavior, performance, and carcass traits were influenced by sex (p < 0.05). Males showed higher dry matter intake (DMI), average daily gain (ADG), mid-test metabolic weight (BW0.75), rib eye area, and rump fat thickness than females, besides spending more time drinking and eating. Low RFI animals exhibited higher DMI than high RFI animals. Low RWI animals ingested 3.89 L/d of water further than high RWI animals. The interaction between sex and RWI influenced the DMI, BW0.75, and backfat thickness. The ingestive behavior of low and high RFI animals was similar, although high RWI animals visited a smaller number of drinkers than low RWI animals. Water intake positively affects productive efficiency, and the combined use of RWI and RFI may help improve the selection of more efficient animals contributing to reducing the costs of beef cattle production and improving environmental sustainability.

5.
Rev. colomb. cienc. pecu ; 33(2): 81-95, Apr.-June 2020. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1289286

ABSTRACT

Abstract Background: Pregnancy in all animal species requires special care and attention. During this period there is great variation in hematological and biochemical parameters. Many times these parameters are misinterpreted as being obtained from non-pregnant animals with unknown parasite status. Objective: To characterize the hematological, biochemical, and parasitological values within the peripartum period of Santa Ines sheep naturally infected. Methods: For this purpose, 45 ewes were used, with an average body weight of 50 kg. Data were collected during pregnancy, birth and, lactation. Measurements included body weight, body condition score (BCS), evaluation of conjunctive staining, and collection of blood and feces. Results: All variables changed throughout physiological stages. Weight and BCS were different between periods (p<0.05). Fecal egg counts (FEC) were higher in the peripartum period, with a predominance of Haemonchus ssp, 92.85%. Mean hematological and biochemical values varied throughout the study, (p>0.05). Conclusion: The influence of peripartum on the parameters studied should be considered and its use as a reference value. Regarding the physiological variations observed during peripartum, proper animal management could help minimizing the negative effects of parasitic infections on productivity.


Resumen Antecedentes: La preñez en todas las especies animales requiere atención y cuidados especiales. En ese período existe gran variación en los parámetros hematológicos y bioquímicos. Muchas veces estos parámetros son interpretados erróneamente por ser obtenidos de animales no gestantes y con estatus parasitario desconocido. Objetivo: Caracterizar los valores hematológicos, bioquímicos y parasitológicos durante el periparto en ovejas Santa Inés infectadas naturalmente. Métodos: Se utilizaron 45 ovejas, con un peso corporal promedio de 50 kg. la recolección de muestras se realizó durante la gestación, el parto y la lactancia. Se evaluó el peso, la condición corporal, la tinción conjuntiva, y se recolectaron muestras de sangre y heces. Resultados: Todas las variables mostraron variaciones a lo largo de las etapas fisiológicas. La puntuación de peso y condición corporal (BCS) mostró diferencia entre períodos (p<0,05). Los recuentos de huevos fecales (FEC) tuvieron mayores promedios en el periparto, con predominio de Haemonchus ssp, 92,85%. Los valores medios hematológicos y bioquímicos variaron a lo largo del estudio (p<0,05). Conclusiones: Se recomienda considerar la influencia del periparto en los parámetros estudiados y su uso como valor de referencia. Con respecto a las variaciones fisiológicas observadas durante el periparto, el manejo adecuado de los animales podría ayudar a minimizar los efectos negativos de las infecciones parasitarias sobre la productividad.


Resumo Antecedentes: A prenhez em todas as espécies requer atenção e cuidados especiais. Neste período há grande variação dos parâmetros hematológicos e bioquímicos dos animais. Muitas vezes estes parâmetros são mal interpretados na realização de diagnósticos por serem baseados em parâmetros de animais saudáveis não gestantes, desconsiderando também a infecção parasitária. Objetivo: Caracterizar os valores hematológicos, bioquímicos e parasitológicos durante o periparto de ovelhas da raça Santa Inês naturalmente infectadas. Métodos: Foram utilizadas quarenta e cinco ovelhas, com peso corporal médio de 50 kg, os animais foram acompanhados durante a prenhez, parto e lactação. As análises compreendiam: pesagem, condição corporal, Famacha©, sangue e fezes. Resultados: Todas as variáveis apresentaram variações concomitantemente ao avanço da gestação, parto e lactação. O peso (PS) e o escore da condição corporal (ECC) apresentaram diferença estatística entre os períodos (p>0,05). As contagens de ovos por grama de fezes (FEC) apresentaram médias mais elevadas no periparto. Os valores hematológicos e bioquímicos também variaram (p>0,05). Conclusão: Devido ao resultado, sugere-se considerar a influência de periparto sobre os parâmetros estudados e a sua utilização como um valor de referência. Tendo em vista as variações fisiológicas devido o período do periparto e as infecções parasitárias o manejo dos animais deve ter como objetivo minimizar os impactos negativos na produção animal.

6.
Trop Anim Health Prod ; 52(5): 2233-2241, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32125597

ABSTRACT

The climate-related problems that affect animal production in tropical countries have encouraged seeking solutions to increase herd productivity and one alternative is the use of breeds adapted to high-temperature environments. The objective of this study was to evaluate the effect of temperature on 77 Caracu and Nelore males submitted to three different environments: morning period (8:00 to 10:00 AM), afternoon in the sun, and afternoon in a shaded environment (11:00 AM to 1:00 PM). The following physiological parameters were measured in each treatment: heart and respiration rates, rectal and dorsal surface temperatures, and cortisol level. The data were analyzed with the MIXED procedure (SAS) and the model included the fixed effects of treatment (morning, sun, and shade), breed (Nelore and Caracu), month of measurement (December and February), and the interaction between effects. A higher dorsal surface temperature was observed in animals of both breeds in the sun treatment compared with the shade treatment. Caracu animals had a higher dorsal surface temperature than Nelore animals, which probably caused the higher rectal temperature observed in the sun treatment compared with the shade treatment in both breeds over the 2 months of the study. All physiological parameters measured in this study were efficient to detect the thermal stress in both breeds. Despite the variations in rectal temperature observed during the treatments, the animals of the two breeds exhibited no significant changes in heart rate, respiration rate, and cortisol level for the maintenance of thermal homeostasis. In conclusion, both breeds were considered tolerant to sun exposure, demonstrating adaptation of these animals to high-temperature environments, without evidence of harm to its health and welfare.


Subject(s)
Body Temperature , Cattle/physiology , Heart Rate , Hydrocortisone/blood , Respiratory Rate , Thermotolerance , Animals , Hot Temperature , Male
7.
J Appl Genet ; 58(1): 103-109, 2017 Feb.
Article in English | MEDLINE | ID: mdl-27262297

ABSTRACT

The aim of this study was to estimate heritability and predict breeding values for longevity among cows in herds of Nellore breed, considering the trait cow's age at last calving (ALC), by means of survival analysis methodology. The records of 11,791 animals from 22 farms were used. The variable ALC has been used by a criterion that made it possible to include cows not only at their first calving but also at their ninth calving. The criterion used was the difference between the date of each cow's last calving and the date of the last calving on each farm. If this difference was greater than 36 months, the cow was considered to have failed and uncensored. If not, this cow was censored, thus indicating that future calving remained possible for this cow. The survival model used for the analyses was the proportional hazards model, and the base risk was given by a Weibull distribution. The heritability estimate obtained was equal to 0.25. It was found that the ALC variable had the capacity to respond to selection for the purpose of increasing the longevity of the cows in the herds.


Subject(s)
Age Factors , Cattle/genetics , Fertility/genetics , Longevity/genetics , Pregnancy, Animal/genetics , Animals , Breeding , Female , Male , Parturition , Pregnancy , Proportional Hazards Models
8.
Reprod Sci ; 23(3): 342-51, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26342050

ABSTRACT

This study evaluated the potential protective effect of the antioxidants, l-carnitine (LC) and N-acetyl-cysteine (NAC), in preventing meiotic oocyte damage induced by follicular fluid (FF) from infertile women with mild endometriosis (ME). We performed an experimental study. The FF samples were obtained from 22 infertile women undergoing stimulated cycles for intracytoplasmic sperm injection (11 with ME and 11 without endometriosis). Immature bovine oocytes were submitted to in vitro maturation (IVM) divided into 9 groups: no-FF (No-FF); with FF from control (CFF) or ME (EFF) groups; and with LC (C + LC and E + LC), NAC (C + NAC and E + NAC), or both antioxidants (C + 2Ao and E + 2Ao). After IVM, oocytes were immunostained for visualization of microtubules and chromatin by confocal microscopy. The percentage of meiotically normal metaphase II (MII) oocytes was significantly lower in the EFF group (51.35%) compared to No-FF (86.36%) and CFF (83.52%) groups. The E + NAC (62.22%), E + LC (80.61%), and E + 2Ao (61.40%) groups showed higher percentage of normal MII than EFF group. The E + LC group showed higher percentage of normal MII than E + NAC and E + 2Ao groups and a similar percentage to No-FF and CFF groups. Therefore, FF from infertile women with ME causes meiotic abnormalities in bovine oocytes, and, for the first time, we demonstrated that the use of NAC and LC prevents these damages. Our findings elucidate part of the pathogenic mechanisms involved in infertility associated with ME and open perspectives for further studies investigating whether the use of LC could improve the natural fertility and/or the results of in vitro fertilization of women with ME.


Subject(s)
Acetylcysteine/pharmacology , Carnitine/pharmacology , Endometriosis/pathology , Follicular Fluid , Infertility, Female/pathology , Oocytes/drug effects , Acetylcysteine/therapeutic use , Adult , Animals , Carnitine/therapeutic use , Cattle , Endometriosis/prevention & control , Female , Humans , Infertility, Female/prevention & control , Meiosis/drug effects , Meiosis/physiology , Oocytes/pathology , Ovulation Induction/methods
9.
Rev. bras. entomol ; 58(3): 273-279, July-Sept. 2014. graf, tab
Article in English | LILACS | ID: lil-724030

ABSTRACT

Comparative abundance and diversity of Dryininae (Hymenoptera, Dryinidae) in three savannah phytophysiognomies in southeastern Brazil, under three sampling methods. This study aimed to assess the abundance and diversity of Dryininae in riparian vegetation, Brazilian savannah, and savannah woodland vegetation at the Estação Ecológica de Jataí, in Luiz Antônio, State of São Paulo, Brazil, by using Moericke, Malaise, and light traps. The sampling was carried out from December 2006 to November 2009, and 371 specimens of Dryininae were caught, with the highest frequencies in spring and summer. Fourteen species of Dryinus Latreille, 1804 and one of Thaumatodryinus Perkins, 1905 were identified. The highest frequencies of Dryinus in the riparian vegetation differed significantly from those obtained in the Brazilian savannah and savannah woodland vegetation. In the riparian vegetation, the highest number of Dryinus was collected using light traps and the interactions between abundance and the collection method used were significant. The number of specimens of Dryinus collected in the Brazilian savannah and savannah woodland vegetation using Malaise traps did not differ significantly from those obtained using Moericke traps. Males significantly outnumbered females in the sex ratio of Dryinus. The species diversity of Dryinus based on females collected using Malaise traps was high in the Brazilian savannah. Furthermore, high species richness of female Dryinus was observed in riparian vegetation (six species) and Brazilian savannah (five). The light trap was the most successful method for sampling diversity of Dryininae.

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